Thursday, 7 July 2011

Bouncing bustards


It was late May and I was taking our guests KY Shum and his partner Cathy Chan from Hong Kong into the field for their last morning in Extremadura. KY had sent me in advance a list of species that they were particularly interested in photographing. One of them was the Little Bustard. I knew of a place about twenty minutes from home where a male Little Bustard was regularly coming out onto a track to display. If we were there at first light, KY should be able to get some pictures. As we approached the track in my vehicle there was no sign of the bird. We stopped and I carefully checked the area. Almost immediately I found it, not on the track but close by in the yellow-dry steppe grasses. KY carefully got out of the vehicle and stood behind the gate at the entrance of the track, with the car behind him, so his outline was invisible. It was perfect early morning light and no sign of heat shimmer. As we watched, the Little Bustard threw its head back as it called, delivering a rather far-carrying sound, like someone blowing a raspberry. Its intention was to attract females with this show. As if rude sounds were not enough, it then jumped up into the air, like a bounce really. As it did its striking black and white neck feathers were erected, giving it almost a cobra-like hood and the largely white flight feathers also added to the visual impact. KY got his photo - a wonderful study of Little Bustard in full display.

Despite the tall vegetation, late spring is one of the best times of the year to see Little Bustards. This is because from late April to mid-May, males are at the apex of their display period and they want to be as highly visible as possible in order to be found and chosen by the highly selective females. They grow their boldly patterned neck plumage, stand on mounds, boulders or anywhere that will enable their heads and necks to stick up above the level of the tall grasses. They call almost incessantly in the morning and the evening. If one stands in good Little Bustard areas one can hear three of four calling at one time and with careful scanning usually find them as well. They will do their bounce, as KY's photo shows and males will also chase each other in a wide circling flight, their wings making a whistling sound, which gives them their Spanish name "Sisón". The females lack the bold neck pattern and can be seen if one carefully checks the vicinity, slowly approaching a favoured male.

The other excellent time to see Little Bustards is in the winter when they form flocks, sometimes of several hundred strong. They prefer to be in fields where there is tall dry vegetation such as dead thistles or stubble and can often be quite well concealed. However, the low morning or evening sunlight will catch the white underparts to reveal the birds' presence.

Sadly, the Little Bustard is in trouble. Over half of the Iberian population occurs in Extremadura and neighbouring Castille La Mancha, more than half of the global population occurs in the peninsular. However, surveys carried out in Extremadura suggest a decline of 75% in just eleven years, and overall across Spain the decline is thought to be about 30% (De Juana, E., 2009 Ardeola 56:119-125). The overall negative trend is probably due to gradual changes in land-use and agricultural practice, but why the decline would be more marked in Extremadura, no one knows. After all, here in many of the steppe areas the land-use practice is still quite traditional, with a slow rotation system, low intensity land-use and mixed farming. The results of the survey match many anecdotal observations of those who have been birding in Extremadura for twenty or more years. It goes to show how important these regular surveys are, but they also need to be followed-up quickly with more in-depth studies of factors that may influence population trends. A morning on the plains in late spring without hearing the Little Bustard call or watching it "bounce" would be unimagineable.

For more of KY's photos go to

https://picasaweb.google.com/kyshum/SpainWildBirds

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